Performance Advisors
When it comes to understanding how to tune WebSphere applications, it often feels like we are running with our headlights off! With IBM WAS, V5.0.2 and V5.1, the Performance Advisors come to the rescue. There are two performance advisors that provide suggestions to help tune systems for optimal performance. Both advisors use the Performance Monitoring Infrastructure (PMI) data to suggest configuration changes to the WebSphere thread pools, connection pools, prepared statement cache, session cache, heap size, etcetera.
The two performance advisors are:
| Runtime Performance Advisor |
| Performance Advisor in Tivoli Performance Viewer (TPV Advisor) |
The first advisor, the Runtime Performance Advisor, which executes in the appserver process, is configured through the WebSphere Administrative Console. Running in the application server's JVM, this advisor periodically checks for inefficient settings, and issues recommendations as standard WebSphere warning messages. These recommendations are displayed both as warnings in the Administrative Console under WebSphere Runtime Messages in the WebSphere Status panel and as text in the SystemOut.log file. Enabling the Runtime Performance Advisor has minimal system performance impact.
The second, the TPV Advisor, runs in the Tivoli Performance Viewer (TPV) and provides recommendations on inefficient settings at a specific point in time. The TPV Advisor provides more extensive advice than the Runtime Performance Advisor. For example, TPV provides advice on setting the dynamic cache size, setting the JVM heap size, and using the DB2 Performance Configuration Wizard.
Table 16-6 gives a summary of the two Performance Advisors.
Table 16-6
| Runtime Performance Advisor | Performance Advisor in Tivoli Performance Viewer (TPV) | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Location of execution | Application server | TPV client | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Location of tool | Administrative console | TPV | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Output | SystemOut.log file and WebSphere run-time messages in WebSphere status panel in the Administrative Console | TPV graphical user interface (GUI) | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Frequency of operation | Every 10 seconds in background | When you select to refresh in TPV | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Types of advice |
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Performance advisors summary
Figure 16-32 shows the simplified architecture of the Performance Advisors.
Figure 16-32 Simplified performance advisors architecture
For more information about PMI and TPV, refer to 16.2, Performance Monitoring Infrastructure and 16.3, Using Tivoli Performance Viewer.
WebSphere is a trademark of the IBM Corporation in the United States, other countries, or both.
IBM is a trademark of the IBM Corporation in the United States, other countries, or both.
Tivoli is a trademark of the IBM Corporation in the United States, other countries, or both.